Livestock producers frequently utilize automatic feeding systems to assure that the animals, especially small animals, are always supplied with adequate feed for healthy and rapid growth. In the case of baby pigs, the feed is frequently supplied in a liquid form, usually milk or a milk replacer. The liquid feeding systems that are presently in use provide the liquid to individual drinker units from a supply tank, the drinker units permitting the animals to drink on a need basis by actuating a valve that allows the milk to flow into the unit. In presently known systems, each drinker unit is connected by a vertical line to an overhead trunk or supply line, the milk being supplied to each drinker unit. An example of such a system is shown in my U.S. Pat. No. 5,115,764. Although systems of this type assure a constant supply of the liquid feed to the animals, when the ambient air temperature is low and remains low for an extended period of time, the temperature of the liquid will also be lowered and may not be as palatable to small, baby animals who prefer warm, liquid feed. The baby animals may therefore not consume the amount of liquid feed desired for proper growth.
Therefore, there is a need for an improved system for supplying heated liquid feed to individual drinker units from a supply source, which system will provide the heated liquid feed to the drinker units at a temperature desired by the baby animals.
Because the liquid feed is circulated under pressure through all of the lines to prevent the liquid feed from remaining in any portion of the lines and thus becoming stale or clogging the lines, there is a need for a system in which the liquid feed is heated without creating a hazard if the controls should fail and the heating means fail to shut down at the proper time.
Because systems of this type must be regularly cleaned, and if difficult to clean may be neglected by the livestock producer, there is also a need for a heated system which can be easily cleaned in place.